While newer,more efficient Lithium-ion batteries(LIBs)and extinguishing agents have been developed to reduce the occurrence of thermal runaway accidents,there is still a scarcity of research focused on the application...While newer,more efficient Lithium-ion batteries(LIBs)and extinguishing agents have been developed to reduce the occurrence of thermal runaway accidents,there is still a scarcity of research focused on the application of surfactants in different LIBs extinguishing agents,particularly in terms of patented technologies.The aim of this review paper is to provide an overview of the technological progress of LIBs and LIBs extinguishing agents in terms of patents in Korea,Japan,Europe,the United States,China,etc.The initial part of this review paper is sort out LIBs technology development in different regions.In addition,to compare LIBs extinguishing agent progress and challenges of liquid,solid,combination of multiple,and microencapsulated.The subsequent section of this review focuses on an in-depth analysis dedicated to the efficiency and challenges faced by the surfactants corresponding design principles of LIBs extinguishing agents,such as nonionic and anionic surfactants.A total of 451,760 LIBs-related patent and 20 LIBs-fire-extinguishing agent-related patent were included in the analyses.The extinguishing effect,cooling performance,and anti-recombustion on different agents have been highlighted.After a comprehensive comparison of these agents,this review suggests that temperature-sensitive hydrogel extinguishing agent is ideal for the effective control of LIBs fire.The progress and challenges of surfactants have been extensively examined,focusing on key factors such as surface activity,thermal stability,foaming properties,environmental friendliness,and electrical conductivity.Moreover,it is crucial to emphasize that the selection of a suitable surfactant must align with the extinguishing strategy of the extinguishing agent for optimal firefighting effectiveness.展开更多
Silicon carbide(SiC) power modules play an essential role in the electric vehicle drive system. To improve their performance, reduce their size, and increase production efficiency, this paper proposes a multiple stake...Silicon carbide(SiC) power modules play an essential role in the electric vehicle drive system. To improve their performance, reduce their size, and increase production efficiency, this paper proposes a multiple staked direct bonded copper(DBC) unit based power module packaging method to parallel more chips. This method utilizes mutual inductance cancellation effect to reduce parasitic inductance. Because the conduction area in the new package is doubled, the overall area of power module can be reduced. Entire power module is divided into smaller units to enhance manufacture yield, and improve design freedom. This paper provides a detailed design, analysis and fabrication procedure for the proposed package structure. Additionally, this paper offers several feasible solutions for the connection between power terminals and DBC untis. With the structure, 18dies were paralleled for each phase-leg in a econodual size power module. Both simulation and double pulse test results demonstrate that, compared to conventional layouts, the proposed package method has 74.8% smaller parasitic inductance and 34.9% lower footprint.展开更多
High-performance Cu/Graphene composite wire synergistically strengthened by nano Cr_(3)C_(2) phase was directly synthesized via hot press sintering followed by severe cold plastic deformation, using liquid paraffin an...High-performance Cu/Graphene composite wire synergistically strengthened by nano Cr_(3)C_(2) phase was directly synthesized via hot press sintering followed by severe cold plastic deformation, using liquid paraffin and CuCr alloy powder as the raw materials. Since graphene is in situ formed under the catalysis of copper powder during the sintering process, the problem that graphene is easy to agglomerate and difficult to disperse uniformly in the copper matrix has been solved. The nano Cr_(3)C_(2)-particles nailed at the interface favor to improve the interface bonding. The Cu/Graphene composite possesses high electrical conductivity, hardness, and plasticity. The composite wire exhibits high electrical conductivity of 96.93% IACS, great tensile strength of 488MPa, and excellent resistance to softening. Even after annealing at 400℃ for 1 h, the tensile strength can still reach 268 MPa with a conductivity of about 99.14% IACS.The wire's temperature coefficient of resistance(TCR) is largely reduced to 0.0035/℃ due to the complex structure,which leads the wire to present low resistivity at higher temperatures. Such Cu/Graphene composite wire with excellent comprehensive performance has a good application prospect in high-power density motors.展开更多
Purpose:Nowadays,public opinions during public emergencies involve not only textual contents but also contain images.However,the existing works mainly focus on textual contents and they do not provide a satisfactory a...Purpose:Nowadays,public opinions during public emergencies involve not only textual contents but also contain images.However,the existing works mainly focus on textual contents and they do not provide a satisfactory accuracy of sentiment analysis,lacking the combination of multimodal contents.In this paper,we propose to combine texts and images generated in the social media to perform sentiment analysis.Design/methodology/approach:We propose a Deep Multimodal Fusion Model(DMFM),which combines textual and visual sentiment analysis.We first train word2vec model on a large-scale public emergency corpus to obtain semantic-rich word vectors as the input of textual sentiment analysis.BiLSTM is employed to generate encoded textual embeddings.To fully excavate visual information from images,a modified pretrained VGG16-based sentiment analysis network is used with the best-performed fine-tuning strategy.A multimodal fusion method is implemented to fuse textual and visual embeddings completely,producing predicted labels.Findings:We performed extensive experiments on Weibo and Twitter public emergency datasets,to evaluate the performance of our proposed model.Experimental results demonstrate that the DMFM provides higher accuracy compared with baseline models.The introduction of images can boost the performance of sentiment analysis during public emergencies.Research limitations:In the future,we will test our model in a wider dataset.We will also consider a better way to learn the multimodal fusion information.Practical implications:We build an efficient multimodal sentiment analysis model for the social media contents during public emergencies.Originality/value:We consider the images posted by online users during public emergencies on social platforms.The proposed method can present a novel scope for sentiment analysis during public emergencies and provide the decision support for the government when formulating policies in public emergencies.展开更多
THE rapid growth of new energy vehicles is accelerating the low-carbon transition in the global transportation sector. According to the international energy agency report, more than 10 million electric vehicles(EVs) i...THE rapid growth of new energy vehicles is accelerating the low-carbon transition in the global transportation sector. According to the international energy agency report, more than 10 million electric vehicles(EVs) including pure electric and hybrid models were sold worldwide in 2022, which means that the global share of electric vehicles in the overall automotive market has risen from less than 5% in 2020 to 14% in 2022.展开更多
The differences in the microstructure and elevated temperature tensile properties of gravity die cast,squeeze cast,and semi-solid thixoformed Al-Si-Cu-Mn-Fe alloys after thermal exposure at 300℃were discussed.The res...The differences in the microstructure and elevated temperature tensile properties of gravity die cast,squeeze cast,and semi-solid thixoformed Al-Si-Cu-Mn-Fe alloys after thermal exposure at 300℃were discussed.The results demonstrate that the elevated temperature tensile properties of semi-solid thixoformed alloys were significantly higher than those of gravity die cast and squeeze cast alloys,especially after thermal exposure for 100 h.The ultimate tensile strength(UTS)of semi-solid thixoformed alloys after thermal exposure at 300℃for 0.5,10 and 100 h were 181,122 and 110 MPa,respectively.The UTS values of semi-solid thixoformed alloys were higher than those of heat resistant aluminum alloys used in commercial applications.The enhanced elevated temperature tensile properties of semi-solid thixoformed experimental alloys after thermal exposure can be attributed to the combined reinforcement of precipitation strengthening and grain boundary strengthening due to thermally stable intermetallic phases as well as suitable grain size.展开更多
The bending responses of functionally graded （FG） nanobeams with simply supported edges are investigated based on Timoshenko beam theory in this article. The Gurtin-Murdoch surface elasticity theory is adopted to an...The bending responses of functionally graded （FG） nanobeams with simply supported edges are investigated based on Timoshenko beam theory in this article. The Gurtin-Murdoch surface elasticity theory is adopted to analyze the influences of surface stress on bending response of FG nanobeam. The material properties are assumed to vary along the thickness of FG nanobeam in power law. The bending governing equations are derived by using the minimum total potential energy principle and explicit formulas are derived for rotation angle and deflection of nanobeams with surface effects. Illustrative examples are implemented to give the bending deformation of FG nanobeam. The influences of the aspect ratio, gradient index, and surface stress on dimensionless deflection are discussed in detail.展开更多
Objective miR-22 is highly active in breast cancer, especially in the luminal B and HER2 subtypes.However, the detailed potential of the use of target genes for miR-22 in breast cancer are still unclear. Inthis study,...Objective miR-22 is highly active in breast cancer, especially in the luminal B and HER2 subtypes.However, the detailed potential of the use of target genes for miR-22 in breast cancer are still unclear. Inthis study, we aimed to discover potential genes and the miRNA-DEGs network of miR-22 in breast cancerusing bioinformatics approaches.Methods Analysis of microarray data GSE17508 (including 3 miR-22 knockout samples and 3 controls)obtained from the Gene Expression Omnibus (GEO) database was performed. Differentially expressedgenes (DEGs) between the miR-22 knockout samples and the three control samples were detected usingGEO2R. The gene ontology (GO) functional enrichment analysis and protein-protein interaction (PPI)network of DEGs were performed using the online tool Metascape and STRING database, separately. ThemiR-22 and DEG networks were obtained from the miRNet database. Cytoscape software was used toconstruct and analyze a merged miRNA-DEG network. The online tools database, mirDIP 4.1, was used topredict miR-22 target genes.Results Certain DEGs and miRNAs may be potential targets for predicting and treating miR-22 expressedbreast cancer.Conclusion We constructed a prognostic model of rectal adenocarcinomas based on four immunerelatedlncRNAs by analyzing the data based on TCGA database, with high prediction accuracy. We alsoidentified two biomarkers with poor prognosis (PXN-AS1 and AL158152.2) and one biomarker with goodprognosis (LINC01871).展开更多
基金supported by the National Key Research and Development Program of China (No.2017YFC0804700)the Opening Project of State Key Laboratory of Explosion Science and Technology,Beijing Institute of Technology (No.KFJJ23-23M)。
文摘While newer,more efficient Lithium-ion batteries(LIBs)and extinguishing agents have been developed to reduce the occurrence of thermal runaway accidents,there is still a scarcity of research focused on the application of surfactants in different LIBs extinguishing agents,particularly in terms of patented technologies.The aim of this review paper is to provide an overview of the technological progress of LIBs and LIBs extinguishing agents in terms of patents in Korea,Japan,Europe,the United States,China,etc.The initial part of this review paper is sort out LIBs technology development in different regions.In addition,to compare LIBs extinguishing agent progress and challenges of liquid,solid,combination of multiple,and microencapsulated.The subsequent section of this review focuses on an in-depth analysis dedicated to the efficiency and challenges faced by the surfactants corresponding design principles of LIBs extinguishing agents,such as nonionic and anionic surfactants.A total of 451,760 LIBs-related patent and 20 LIBs-fire-extinguishing agent-related patent were included in the analyses.The extinguishing effect,cooling performance,and anti-recombustion on different agents have been highlighted.After a comprehensive comparison of these agents,this review suggests that temperature-sensitive hydrogel extinguishing agent is ideal for the effective control of LIBs fire.The progress and challenges of surfactants have been extensively examined,focusing on key factors such as surface activity,thermal stability,foaming properties,environmental friendliness,and electrical conductivity.Moreover,it is crucial to emphasize that the selection of a suitable surfactant must align with the extinguishing strategy of the extinguishing agent for optimal firefighting effectiveness.
基金supported in part by National Key R&D Program of China (2021YFB2500600)CAS Youth multi-discipline project (JCTD-2021-09)Strategic Piority Research Program of Chinese Academy of Sciences (XDA28040100)。
文摘Silicon carbide(SiC) power modules play an essential role in the electric vehicle drive system. To improve their performance, reduce their size, and increase production efficiency, this paper proposes a multiple staked direct bonded copper(DBC) unit based power module packaging method to parallel more chips. This method utilizes mutual inductance cancellation effect to reduce parasitic inductance. Because the conduction area in the new package is doubled, the overall area of power module can be reduced. Entire power module is divided into smaller units to enhance manufacture yield, and improve design freedom. This paper provides a detailed design, analysis and fabrication procedure for the proposed package structure. Additionally, this paper offers several feasible solutions for the connection between power terminals and DBC untis. With the structure, 18dies were paralleled for each phase-leg in a econodual size power module. Both simulation and double pulse test results demonstrate that, compared to conventional layouts, the proposed package method has 74.8% smaller parasitic inductance and 34.9% lower footprint.
基金supported by the National Key Research and Development Program of China under Grant2021YFB2500600the Youth Innovation Promotion Association CAS under Grant2022138+2 种基金the National Natural Science Foundation of China under Grant51901221the Institute of Electrical EngineeringCAS under GrantE155710201 and E155710301。
文摘High-performance Cu/Graphene composite wire synergistically strengthened by nano Cr_(3)C_(2) phase was directly synthesized via hot press sintering followed by severe cold plastic deformation, using liquid paraffin and CuCr alloy powder as the raw materials. Since graphene is in situ formed under the catalysis of copper powder during the sintering process, the problem that graphene is easy to agglomerate and difficult to disperse uniformly in the copper matrix has been solved. The nano Cr_(3)C_(2)-particles nailed at the interface favor to improve the interface bonding. The Cu/Graphene composite possesses high electrical conductivity, hardness, and plasticity. The composite wire exhibits high electrical conductivity of 96.93% IACS, great tensile strength of 488MPa, and excellent resistance to softening. Even after annealing at 400℃ for 1 h, the tensile strength can still reach 268 MPa with a conductivity of about 99.14% IACS.The wire's temperature coefficient of resistance(TCR) is largely reduced to 0.0035/℃ due to the complex structure,which leads the wire to present low resistivity at higher temperatures. Such Cu/Graphene composite wire with excellent comprehensive performance has a good application prospect in high-power density motors.
基金This paper is supported by the National Natural Science Foundation of China under contract No.71774084,72274096the National Social Science Fund of China under contract No.16ZDA224,17ZDA291.
文摘Purpose:Nowadays,public opinions during public emergencies involve not only textual contents but also contain images.However,the existing works mainly focus on textual contents and they do not provide a satisfactory accuracy of sentiment analysis,lacking the combination of multimodal contents.In this paper,we propose to combine texts and images generated in the social media to perform sentiment analysis.Design/methodology/approach:We propose a Deep Multimodal Fusion Model(DMFM),which combines textual and visual sentiment analysis.We first train word2vec model on a large-scale public emergency corpus to obtain semantic-rich word vectors as the input of textual sentiment analysis.BiLSTM is employed to generate encoded textual embeddings.To fully excavate visual information from images,a modified pretrained VGG16-based sentiment analysis network is used with the best-performed fine-tuning strategy.A multimodal fusion method is implemented to fuse textual and visual embeddings completely,producing predicted labels.Findings:We performed extensive experiments on Weibo and Twitter public emergency datasets,to evaluate the performance of our proposed model.Experimental results demonstrate that the DMFM provides higher accuracy compared with baseline models.The introduction of images can boost the performance of sentiment analysis during public emergencies.Research limitations:In the future,we will test our model in a wider dataset.We will also consider a better way to learn the multimodal fusion information.Practical implications:We build an efficient multimodal sentiment analysis model for the social media contents during public emergencies.Originality/value:We consider the images posted by online users during public emergencies on social platforms.The proposed method can present a novel scope for sentiment analysis during public emergencies and provide the decision support for the government when formulating policies in public emergencies.
文摘THE rapid growth of new energy vehicles is accelerating the low-carbon transition in the global transportation sector. According to the international energy agency report, more than 10 million electric vehicles(EVs) including pure electric and hybrid models were sold worldwide in 2022, which means that the global share of electric vehicles in the overall automotive market has risen from less than 5% in 2020 to 14% in 2022.
基金financially supported by the National Natural Science Foundation of China(Nos.51704084,52074131)the Science and Technology Plan of Guizhou Province,China(Nos.ZK2021(267),ZK2021(067))the Cultivation Project of Guizhou University,China(No.2019(23))。
文摘The differences in the microstructure and elevated temperature tensile properties of gravity die cast,squeeze cast,and semi-solid thixoformed Al-Si-Cu-Mn-Fe alloys after thermal exposure at 300℃were discussed.The results demonstrate that the elevated temperature tensile properties of semi-solid thixoformed alloys were significantly higher than those of gravity die cast and squeeze cast alloys,especially after thermal exposure for 100 h.The ultimate tensile strength(UTS)of semi-solid thixoformed alloys after thermal exposure at 300℃for 0.5,10 and 100 h were 181,122 and 110 MPa,respectively.The UTS values of semi-solid thixoformed alloys were higher than those of heat resistant aluminum alloys used in commercial applications.The enhanced elevated temperature tensile properties of semi-solid thixoformed experimental alloys after thermal exposure can be attributed to the combined reinforcement of precipitation strengthening and grain boundary strengthening due to thermally stable intermetallic phases as well as suitable grain size.
基金supported by the National Natural Science Foundation of China(11302055)Heilongjiang Post-doctoral Scientific Research Start-up Funding(LBH-Q14046)
文摘The bending responses of functionally graded （FG） nanobeams with simply supported edges are investigated based on Timoshenko beam theory in this article. The Gurtin-Murdoch surface elasticity theory is adopted to analyze the influences of surface stress on bending response of FG nanobeam. The material properties are assumed to vary along the thickness of FG nanobeam in power law. The bending governing equations are derived by using the minimum total potential energy principle and explicit formulas are derived for rotation angle and deflection of nanobeams with surface effects. Illustrative examples are implemented to give the bending deformation of FG nanobeam. The influences of the aspect ratio, gradient index, and surface stress on dimensionless deflection are discussed in detail.
基金Supported by the Joint Fund Project of Hubei Provincial Health Committee(No.WJ2019H510)the Natural Science Foundation of Inner Mongolia Autonomous Region(No.2015MS0877),China.
文摘Objective miR-22 is highly active in breast cancer, especially in the luminal B and HER2 subtypes.However, the detailed potential of the use of target genes for miR-22 in breast cancer are still unclear. Inthis study, we aimed to discover potential genes and the miRNA-DEGs network of miR-22 in breast cancerusing bioinformatics approaches.Methods Analysis of microarray data GSE17508 (including 3 miR-22 knockout samples and 3 controls)obtained from the Gene Expression Omnibus (GEO) database was performed. Differentially expressedgenes (DEGs) between the miR-22 knockout samples and the three control samples were detected usingGEO2R. The gene ontology (GO) functional enrichment analysis and protein-protein interaction (PPI)network of DEGs were performed using the online tool Metascape and STRING database, separately. ThemiR-22 and DEG networks were obtained from the miRNet database. Cytoscape software was used toconstruct and analyze a merged miRNA-DEG network. The online tools database, mirDIP 4.1, was used topredict miR-22 target genes.Results Certain DEGs and miRNAs may be potential targets for predicting and treating miR-22 expressedbreast cancer.Conclusion We constructed a prognostic model of rectal adenocarcinomas based on four immunerelatedlncRNAs by analyzing the data based on TCGA database, with high prediction accuracy. We alsoidentified two biomarkers with poor prognosis (PXN-AS1 and AL158152.2) and one biomarker with goodprognosis (LINC01871).
